Language Development and Behavioral Systems.

We present the core principles of a behavioral systems theory (BST) that incorporates dynamical systems concepts and applies them to a behavior analysis of early language development. The tenets of BST include multiple determinism, coalescent organization, nonlinearity, emergence, phase shifts, and developmental cusps. Developmental changes are marked by the transactions between genetic inheritance, interactional history, current physiological and environmental conditions, and behavior dynamics. Certain key emergent behaviors, known as cusps, enable further cascading development. Contingencies operating in the young child's current social environment are the catalysts for the coalescence of conditions into the early learning of precursors to communication cusps in early childhood including orienting responses, eye contact, joint attention, and social referencing. In turn these social interaction cusps enable the development of organized patterns of verbal behavior that include imitation, mands, tacts, intraverbals, autoclitics, and naming. Some of these emergent patterns are the product of derived relational responding that enable further verbal behavioral cusps to develop. Early language results from an intensive, naturally occurring, skills learning process consisting of a massive number of contingent interactions between the child and the caregivers. This naturally occurring process resembles the use of multiple exemplars procedures employed by experimental researchers in training language skills to children but are employed intuitively by caregivers. These skills facilitate the emergence of new and more advanced sociocognitive skills later in childhood such as perspective taking, the self, and complex rule-following. We recommend further collaborations with other behavioral and developmental scientists. [ABSTRACT FROM AUTHOR]